Roofing and paving material



CYRUS M. \VARREN, OF BROOKLlNE, MASSACHUSETTS.

ROOFING AND PAVING MATERIAL.

SPECIFICATION forming part of Letters Patent No. 234,442, dated November 16, 1880.

Application filed November 25, 1878.

To all whom it may concern 1 Be it known that I, GYRUs M. WARREN, of Brookline, in the county of Norfolk and State of Massachusetts, have invented a new and useful Roofing and Paving Material, with process of manufacturing the same, which invention is fully described in the following specification.

This invention consists in a roofing and pavin g material formed by mixing coal-tar residuum of any suitable consistency or, other equivalent material with one or more practically or relativelynon-volatile oils or fats, such as wax-tailings, neutralized acid tar, animal or vegetable fat or fat-oil, or other substance having similar solvent and non-volatile properties, such as are produced at a suitably high temperature, either as a residuum or distilled product, at'or near the end of the distillation of natural bitumens, bituminous coals, bituminous shales, bituminous schists, or other substances yielding hydrocarbon oils by distillation, or at or near the end of the redistillation of such oils or of the residuums of the same at a high temperature.

To prepare my compound, distill the oils from coal-tar or coaltar pitch, or any equivalent material, carrying the distillation so far as may be desirable or practicable, and yet preserve the complete fusibility of the residuum. Test a sample of the residuum from time to time during the distillation, and from the point at which it is found when cooled to have the consistency desired for the compound note the quantity of oil or distillate removed, and after partial cooling of the residuum-say about 500 to 400 Fahrenheit-either in the still or .in another vessel into which it may be drawn for cooling and mixing, add usually about the same quantity, by measure, of wax-tailings or other equivalent material, heated, preferably, say to 300 Fahrenheit, and then temper the mixture by gradual additions of the wax-tailings to the consistency when cooled either of ordinary roofing or paving cement, or any other desired consistency, agitating the mixture thoroughly from time to time while tempering by means of a revolving agitator or otherwise to produce a homogeneous product.

In carrying out my invention to produce a compound that shall have the non-volatile containing the anthracene.

properties and the most suitable consistency for roofing or for paving purposes, as the case may be, to be mixed with gravel, sand, powdered stone, or other suit-able material to form a paving-concrete, or to spread upon a felted roof as a binding material for gravel, &c., I prefer to carry the distillation of the tar to about 800 Fahrenheit, or so far as may be practicable and preserve the fluidity of the hot residuum, as by so doing I not only remove proportionally more of the objectionable tar-oils, (to be replaced by less volatile ones, as hereinafter stated,) but at the same time obtain a proportionally larger yield of the oils containing anthracene, this being the most valuable product of the tar, and chiefly obtained above 700 Fahrenheit.

' In conducting the distillation I take ot't' from each forty gallons of tar first about two to two and a halt gallons of light oilland water, and then about nine to ten gallons oft-leadoil, thus reaching a distilling temperature of about 650 to 675 Fahrenheit, at aboutwhich point the residuum is such that it will remain soft after cooling, being about the consistency of the harder grade of roofing-pitch, and still I then continue the distillation to take off about five to six gallons of the anthracene-oil, reaching now a tcm perature of aboutSOO Fahrenheit, as above stated, and producing a residuum that is hard and brittle when cold, but greatly improved as an ingredient of rooting and paving cements to be dissolved with non-volatile oils, such as waxtailings or equivalent material. Afterpartial cooling of this residuum I add about seven to eight gallons of the wax-tailings or other equivalent solvent and non-volatile material for every forty gallons of tar employed, varying the proportionsto produce a harder or a softer compound, as may be desired, and tempering as above to the required consistency, which is usually somewhat softer for paving than for roofing purposes.

If fat-oil is employed instead of wax-tailings, an equivalent result, at least so far as relates to the consistency of the residuum, is obtained with aless proportion-say about one-half to two-thirds-of the quantity required of waxtailings, and the compound will havefar greater toughness at low temperatures. It ispreferable, therefore, when the additional expense is not objectionable, to use either a fat-oil or a mixture of fat-oil and wax-tailings, or equivlent material, varying the proportions according to the degree of toughness required.

My compound may be prepared, also, directly from hard-coattar resid u u m by fusing together about three to live parts, by weight, (more or less,) of the residuum and one part (more or less) of wax-tailings or equivalent material, or a )ro1' ortionally smaller quantity of fat or fat-oil, as above indicated, varying the proportions to produce a compound of suitable consistency either for roofing or paving cc ment, as may be required.

The ordinary coal-tar roofing or paving pitch or cement, or a variety still less soft made for other purposes, (which are prepared by simply distilling oils from the tar till the residuum has acquired the desired consistency, being in either case a more or less sot't-coal'tar residuum,) may be somewhat improved for rooting and paving purposes by adding a portion of the \vax-tailings,tat, or fatoil, or a mixture of two or more of these, or equivalent material, so much in quantity as the consistency of the required cement may permit. This will preserve somewhatits toughness and durability.

I do not confine myself to the proportions above stated, nor to the exact process described; but I may vary these or either of them, as may seem desirable for auy purpose.

I may add the wax-tailings or equivalent material directly to the tar or coal-tar pitch, either in a still or an open vessel, and by application of heat expel the coal-tar oils and other volatile bodies, most of which, having lower boiling-points, will, for the most part, come off first, leaving the wax-tailings mixed with the coal-tar residuum and producing a similar result or compound as by the process above described. In such distillation, however, as the temperature rises more or less of the waxtailings or decomposition products thereof will come oil" with the tar-oils, owingpartly to the tendency of the heavier petroleum products to break upin distillation into bodies of lower boiling-points, yet not enough in this process to perceptibl y affect the result above described. By proceeding in this manner, adding to the tar, or to an equivalent quantity ot' the ordinary coal-tar roofing-pitch, a snflicient quantity of the wax-tailin gs at the outset to, say, an amount equal to about onethird to two-thirds of the weight of the tar, or one-half to an equal weight of the roofingpitch, as the case may be, according to the quantity of anthracene-oil that it is intended to distill off, and also according to the consistency required for the residuum, I may thus obtain directly a residuum of any desired consistency, and at the same time any desired quantity of anthracene-oi], limited only by the quantity of the latter that the tar or is capable of yieldin the pitch If it is intended to distill off the maximum quantity of anthraceneoil, and at the same time leave the residuum of suitable consistency for rooting or paving cement, it would require a weight of wax-tailings nearly or quite equal to the weight of roofing-pitch taken, or equal to the same contained in the tar employed, as the case may be, which is about two-thirds of its weight. To obtain a residuum of about the same consistency and take off only about one-half as much ofanthracene-oil, or to obtain a hard and brittle residuum, (about the same in this respect as would result from distilling off from tar alone about one-half of the anthracene-oil above indicated,) the maximum quantity of wax-tailings in either case would suffice and these proportions may be varied to produce any intermediate results, as may bc'required.

On account of the fact, however, that waxtailings distilled by itself, and apparently, also, when distilled in combination with coal-tar, is to a considerable extent converted into pitch, 1 do not recommend its use for obtaining an additional quantity of anthracene unless this substance and the associated oils command a high price; nor do I limit myself to the use of wax-tailings, fats, or fat-oils as softening material; but may use neutralized acid tar, or any other oil or mixture of oils, or any other substance possessing the same or similar solvent and non-volatileproperties-viz., that of being practically non-volatile at any ordinary tem iierature, or less so than the oils naturally contained in the coal-tar pitch, and which are chiefly removed by this process-and also the property of dissolving and making a homogeneous mixture with hotcoal-tar residuums, and which will not decompose on cool mg.

I may soften the coottar residuum either with pine or other wood tar, rosin oil, orother equivalent material; but the resulting product, though improved, will be far inferior in nondrying properties, hence in durability, to the material produced as above described.

1 may substitute for the coal-tar residuum rosin (or a mixture of rosin and coal-tar residuum) or equivalent material in the preparation of a compound which will be equivalent in the valuable properties specified, and which, by dilution with oil, may be made suitable also for saturating paper or felt; but such compound of rosin and wax-tailings is already covered, under the doctrine of equivalents, by my Patent No. 179,829, dated July 11, 1876, wax-tailings and fat-oil being clearly but equivalents, especially in non-volatile and solvent properties, (the latter with reference to rosin,) for the heavy oil or the tarry residuum of petroleum or candle-tar specified in the patent here referred to. Indeed, the wax-tailings are in reality a heavy oil of petroleum, and, for the purposes for which it is here employed with rosin, fat-oil is butits equivalent.

\Vax-tailings is the name generally given to the final product of the distillation either of petroleum or petroleum residuumusuall y the latter-when the distillation is carried nearly or quite to dryness, leaving a residue of coke. A similar product might probably also be obtained by distillation of other similar hydrocarbon oils, residnums, or paraffines under similar conditions. This product, which is obtained in the proportion of less than two per cent. of the petroleum residuum and less than two-tenths of one per cent. of the petroleum, I find to be quite variable in physical properties, especially when comparing the products of different manufacturers. \Vith some it really is of a waxy consistency, which would naturally suggest its name, or that of stillwax or wax-cokings. With others it is so solid as to have entirely lost its waxy character when cold, and become quite hard; and with others still it is fluid at the common temperature, even at 50 Fahrenheit or under, although at this temperature some samples contain more or less of solid matter in suspension, similar in these respects to ordinary petroleum residuum. The degree ofits fluidity, therefore-2'. 6., ofthe liquid variety-is variable with the temperature, and the consistency of all no doubt depends on the conditions attending their produotiont'. 0., the points or temperatures between which they are collected respectively; but the liquid kind does not become in any degree waxy, even when cooled to 5 below zero, Fahrenheit, at which temperature its consistency resembles that of petroleum residuum at the same temperature. Some manufacturers only collect separately the hard or the waxy variety, preferring, I presume, to run the fluid kind into the heavy oil; and others only collect the fluid variety separately, either interrupting the distillation before much, if any, of the waxy variety has formed, or they let this run into the liquid kind, in which it would probably dissolve. At moderately low temperatures, even as high as 50 to (50 Fahrenheit, with some samples, the liquid variety of wax-tailin gs is found to contain a considerable quantity of crystals in suspension, resembling paraffine in appearance, but having a higher melting-point. These gradually dissolve as the temperature rises, becoming again a homogeneous fluid at the common temperature. Itis this liquid product of 'wax-tailings, which may contain in solution more or less of the hard and of the waxy variety, that I have employed, and prefer to employ, in the preparation of my compound.

Neutralized-acid tar or slnd ge-acid tar is the tarry or oily matter separated from its combination with the acid employed in purifying paraffine-oils and similar material. I have discovered that this substance possesses the property of dissolving with the coal-tar residuums, both the hard and the pitchy variety, by the aid of heat, and remain combined after cooling, differing in this latter respect from both the ordinary residuums and the heavy oils of petroleum, while as solvents for asphaltum and rosin, on the contrary, I find that these substances are all the equivalents of each other. The \vax-tailin gs, however, although distilling at a higher temperature and having a higher specific gravity than the more common and more abundant of the heavy oils of petroleum, nevertheless contain, contrary to the opinion of some, more matter that may be volatilized in a given time under212 Fahrenheit, and probably, therefore, is somewhat inferior as a non-volatile constituent of cements, and the same statements are true also with reference to wax-tailings as compared with the more common residuum of petroleum or petroluin-tar.

I am aware that Allen T. Perry has claimed in his Patent No. 214,312 certain mixtures of waxtailings or still-wax with coal-tar and with coal-tar cement or pitch; but my compound differs essentially from any that he describes or claims, not only in the character of the compound itself, but also in the properties of the ingredients. The wax-tailings or still-wax that he used is described as being of a very thick waxy tenacious character and a fixed unchanging material, which only melts at a very considerable degree of heat. Hence it is one only suitable for mixing with a material that is already soft, and could not serve to soften to the proper consistency, either for rooting or paving cement, the hard and brittle residuum that I employ, which requires for this purpose a material thatis liquid at the common temperature, this being the character of the wax-tailings that I employ. He uses, therefore, to mix with his still-wax, a coal-tar cement or pitch that is still soft with the natural and relatively volatile oils of the tar, while, on the contrary, I employ a hard and brittle residuum from which these oils have been removed at a high temperature. His process also differs essentially from mine, inasmuch as he stops his distillation at about the point or but little above that at which mine essentially begins for the elimination of the natural pitch-oils and anthracene, which latter substances, therefore, he does not obtain.

I am also aware of the patent of Lewis Peirce, No. 179,131, and that of John B. IVands, No. 17,851; but my compound with fat-oil is es sentially different from either of the compounds described in the patents here referred to.

I clainras my invention- 1. The process of manufacturing a compound produced by eliminating oils from coaltar pitch or residuum and substituting liquid wax-tailings or other equivalent non-volatile material, substantially as set forth.

2. The process of producing anthracene-oils by the distillation ofamixture of coal-tar or coaltar pitch and liquid wax-tailin gs or other equivalent nonvolatile material, substantially as set forth.

3. A roofing and paving compound produced by eliminating oils from coal-tar pitch or residuum and substituting liquid wax-tailings a hard-coal-tar residuum, as an ingredient in the manufacture of roofs and pavements, substantially as set forth.

7. Liquid wax-tailings or its equivalent, in combination with coal'tar pitch or softcoal-tar residuum, as an in gredientin the manufacture of roofs and pavements, substantially as set 20 forth.

CYRUS M. \VARREN.

Witnesses:

ALLEN LINCOLN, THOs. J. HIND. 

